Large scale quantum walks by means of optical fiber cavities

TL;DR

This paper presents a novel optical fiber cavity platform for large-scale quantum walks, achieving low losses, high fidelity, and reconfigurability, enabling complex multi-walker and multidimensional quantum simulations.

Contribution

The authors introduce a reconfigurable fiber-optic cavity system for quantum walks, overcoming previous limitations in scale, loss, and flexibility.

Findings

Achieved large number of steps with low loss and high fidelity.

Demonstrated reconfigurable coin bias in the system.

Extended the platform to multidimensional lattices.

Abstract

We demonstrate a platform for implementing quantum walks that overcomes many of the barriers associated with photonic implementations. We use coupled fiber-optic cavities to implement time-bin encoded walks in an integrated system. We show that this platform can achieve very low losses combined with high-fidelity operations, enabling an unprecedented large number of steps in a passive system, as required for scenarios with multiple walkers. Furthermore the platform is reconfigurable, enabling variation of the coin, and readily extends to multidimensional lattices. We demonstrate variation of the coin bias experimentally for three different values.